Two resistors X and Y with 2 ohm and 3 ohm resistances respectively are first connected parallelly and then in series. In both cases, voltage supplied is 5V.

Two resistors X and Y with 2 Ω and 3 Ω resistances respectively are first connected parallelly and then in series. If voltage supplied is 5V, then:

(i) Draw the circuit diagram in order to depict the combination of resistors:

Resistance

Resistance

(ii) Estimate voltage across the 3 Ω resistor in the series combination of resistors.

  • Resistance of X = R1 = 2Ω
  • Resistance of Y = R2 = 3Ω
  • Voltage, V = 6V

In order to find the voltage across a 3Ω resistor in the series combination of resistors, we have to

We are already aware that the equivalent resistance (total resistance) in a series combination can be expressed as:

Req = R+ R2

Now, after replacing the values of R1 and R2 we will get:

⇒ Req= 2 + 3

Req = 5Ω

We know that current can be expressed as:

I = V/R

Here, I = V/Req

So, inserting the given values, we will get:

I = 55

I = 1A

Therefore, the current passing through the circuit is 1A.

Now, in order to find the voltage present across 3Ω resistors, we can also use the formula of voltage:

V = I × R

Now, after placing the required values, we get:

⇒ V = 1 × 3

⇒ V = 3V

Hence, the voltage across the 3Ω resistor is 3 Volts.


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